// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// This class simulates a slow download. Requests to |kUnknownSizeUrl| and
// |kKnownSizeUrl| start downloads that pause after the first N bytes, to be
// completed by sending a request to |kFinishDownloadUrl|.

#ifndef NET_TEST_URL_REQUEST_URL_REQUEST_SLOW_DOWNLOAD_JOB_H_
#define NET_TEST_URL_REQUEST_URL_REQUEST_SLOW_DOWNLOAD_JOB_H_

#include <stddef.h>

#include <set>
#include <string>

#include "base/lazy_instance.h"
#include "base/memory/weak_ptr.h"
#include "net/url_request/url_request_job.h"

namespace net {

class URLRequestSlowDownloadJob : public URLRequestJob {
public:
    // Test URLs.
    static const char kUnknownSizeUrl[];
    static const char kKnownSizeUrl[];
    static const char kFinishDownloadUrl[];
    static const char kErrorDownloadUrl[];

    // Download sizes.
    static const int kFirstDownloadSize;
    static const int kSecondDownloadSize;

    // Timer callback, used to check to see if we should finish our download and
    // send the second chunk.
    void CheckDoneStatus();

    // URLRequestJob methods
    void Start() override;
    bool GetMimeType(std::string* mime_type) const override;
    void GetResponseInfo(HttpResponseInfo* info) override;
    int ReadRawData(IOBuffer* buf, int buf_size) override;

    // Returns the current number of URLRequestSlowDownloadJobs that have
    // not yet completed.
    static size_t NumberOutstandingRequests();

    // Adds the testing URLs to the URLRequestFilter.
    static void AddUrlHandler();

private:
    class Interceptor;

    // Enum indicating where we are in the read after a call to
    // FillBufferHelper.
    enum ReadStatus {
        // The buffer was filled with data and may be returned.
        BUFFER_FILLED,

        // No data was added to the buffer because kFinishDownloadUrl has
        // not yet been seen and we've already returned the first chunk.
        REQUEST_BLOCKED,

        // No data was added to the buffer because we've already returned
        // all the data.
        REQUEST_COMPLETE
    };

    URLRequestSlowDownloadJob(URLRequest* request,
        NetworkDelegate* network_delegate);
    ~URLRequestSlowDownloadJob() override;

    ReadStatus FillBufferHelper(IOBuffer* buf, int buf_size, int* bytes_written);

    void GetResponseInfoConst(HttpResponseInfo* info) const;

    // Mark all pending requests to be finished.  We keep track of pending
    // requests in |pending_requests_|.
    static void FinishPendingRequests();
    static void ErrorPendingRequests();
    typedef std::set<URLRequestSlowDownloadJob*> SlowJobsSet;
    static base::LazyInstance<SlowJobsSet>::Leaky pending_requests_;

    void StartAsync();

    void set_should_finish_download() { should_finish_download_ = true; }
    void set_should_error_download() { should_error_download_ = true; }

    int bytes_already_sent_;
    bool should_error_download_;
    bool should_finish_download_;
    scoped_refptr<IOBuffer> buffer_;
    int buffer_size_;

    base::WeakPtrFactory<URLRequestSlowDownloadJob> weak_factory_;
};

} // namespace content

#endif // NET_TEST_URL_REQUEST_URL_REQUEST_SLOW_DOWNLOAD_JOB_H_
